The present invention relates generally to directive radar systems, and more particularly to steerable antenna arrays.
Phased arrays offer considerable flexibility to a radar system. With complete control of phase to every element of the aperture, the radar beam may be steered rapidly through a wide range of scan-angles. High data rates are available for adaptively interlaced functions including fire-control, surveillance and even communications. A phased array radar may interact freely with a multiplicity of targets under a variety of conditions and adjust its time allocations to give preference to the most pressing immediate needs. That phased arrays have not proliferated is due to their very high cost. With traditional phased arrays using high power tubes, typically about 30 to 40% of the total radar cost is accounted for by the antenna, mainly due to the cost of the phase-shifters, and about 40 to 50% of the cost is due to the transmitter.
With conventional phased arrays, shipboard applications present a problem because of obstructions caused by the superstructure.